Regulating apparatus



Aug. 29, 1933.

A. V. LIVINGSTON REGULATING APPARATUS .Original Filed May 28. 1926 E- /5 Q 52 /2 27 L I I ATTORNEY Patented Aug. 29, 1933 UNITED STATES PATENT DFFICE REGULATING APPARATUS Original application May 28, 1926, Serial No.

112,219. Divided and this application September 26, 1930. Serial No. 484,552

8 Claim.

This invention relates to electrical systems of distribution, and more particularly to car lighting systems in which the generator may be driven, for example, from a car axle.

One of the objects of this invention is to provide a system of the above-mentioned character in which apparatus of simple construction and of thoroughly dependable action may be employed for efliciently and dependably safeguarding the system and translating devices associated therewith against changes in the electrical conditions. Another object is to provide a system of the above-mentionedcharacter which will be of thorough y dependable action and well adapted to meet the widely varying conditions of practical use. Another object is to provide a regulator in which is included a variable resistance preferably in the form of a compressible carbon pile which will be of simple construction and highly sensitive action. Another object is to provide a regulator of the above-mentioned nature capable of rapid and powerfulresponse to the variations or changes in the electrical conditions which it is adapted to rectify, and to achieve these objects in a thoroughly practical way and with simple and dependable apparatus. Other objects will be in part obvious or in part pointed out hereinafter.

This application is a division of my co-pending application Serial No. 112,219, filed May 28,

1926, which has since matured into Patent No.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements'of parts as will be exempliiied in the .structure to be hereinafter described and the scope of the application of which will be indicated in the following claims.

In the accompanying drawing, in which are shown several of the possible embodiments of my invention;

Figure 1 is a diagrammatic representation of the circuit arrangements and of the apparatus illustrative of certain features of my invention as embodied in a car lighting system, and

Figure 2 is a like representation of a modifled and preferred form of system and apparatus.

Similar reference characters refer to similar parts throughout the several views of the drawing.

Referring now to the drawing and more particularly to Figure 1, there is shown at 10 a generator adapted to be driven, in a car lighting system, from a car axle, for example; the generator 10 may be of the shunt wound type and is provided with a shunt field 11 supplied with exciting current through a variable resistance preferably taking the form of a compressible carbon pile 12. The generator 10 is connected to the main line conductors 13 and 14 and may supply energy to a storage battery 15 and to lamps 16, an automatic switch generally indicated at 17 being provided for connecting the generator to the battery and lamps when the voltage of the generator reaches a predetermined value and for disconnecting the generator therefrom when the voltage drops to a predetermined value. This automatic switch 17 may take any suitable or appropriate form. Preferably also, there is interposed between the battery 15 and the lamps 16 a regulator generally indicated at 18; this regulator 18 may also take any suitable or appropriate form, and is adapted to maintain substantially constant the voltage across the lamps 16 throughout such changes in voltage across the battery 15 as are due to the change in the state of charge of the battery or as are due to such conditions as depend upon whether the battery is being charged or not.

Operative upon the carbon pile 12 is a lever 19 pivoted as at 20 and at substantially like distances from the pivot point 20, there are connected to the lever 19 the cores 21 and 22 of two solenoids; the lever 19 is provided with an arm 23 for engaging the movable end of the carbon pile 12, and the lever 19 with its associated solenoid cores is preferably so arranged as to form a substantially balanced mechanical system. In order, however, to maintain the carbon pile 12 under some degree of compression when the generator 10 is at rest or starting up, the mechanical system operative upon thecarbon pile 12 is preferably somewhat out of balance, and such an out of balance condition may be achieved by means of a weight 24 attached to the lever 19 and at such a position as to tend to compress the carbon pile 12.

Operative upon the cores 21 and 22 are appropriate windings arranged to be responsive to those electrical changes in the system which are intended to be rectified, and by way of illustration, the windings are shown as being responsive to changes in the voltage. About the core 22 are two windings 25 and 26, adapted to coact' one with the other and about the core 21 is a winding 27. At this point it might be noted that the solenoids are preferably so constructed and designed as to give a substantially constant pull at the normal voltage and in all positions of the movable core throughout the operating range of the latter.

The windings 25 and 27 are preferably connected in series with each other but through a variable resistance 28 and the filament '29 of a thermionic device 30, preferably of the twoelement type, and having an appropriate anode or plate 31 coacting with the other cathode 29. The circuit of the windings 25 and 27 will thus be seen to be as follows: From one side of the generator 10, as from the main line conductor 14, then conductor 32, filament 29,. adjustable resistance 28, winding 25, conductor 33, winding 27, conductor 34 and thence to theother main line conductor 13 and hence to the other side of the generator 10. Changes in voltage of the system, therefore, will affect in like degree the heating of the filament cathode 29 and also the energization of windings 25 and 27 of the two solenoids, the latter acting, as will be clear, in opposition to each other.

The circuit of the winding 26, which coacts with the winding 25, upon the core 22, is included in the plate circuit of the thermionic device 30 and will be seen to be substantially as follows:-- From one terminal of winding 26, adjustable resistance 28, cathode 29, thence through the available electron path of the device 30 to the plate 31, conductor 35, secondary winding 36 of an appropriate transformer, and thence to the terminal of the coil 26. A condenser 37a, bridged across the coil 26 acts to smooth out the half-waves of the current flowing in they I plate circuit due to the appropriately high alternating potential supplied in the plate circuit by the secondary winding 36 of the transformer.

The primary winding 3'7 of the transformer 3637 is connected by conductors 38 and 39 to a suitable source of alternating current. This source may take the form of a converter or motor-generator operated from the main line conductors of the system, as will be made more clear hereinafter in connection with Figure 2, or it may take the form of the armature of the generator 10 itself, it being understood that the armature windings of the generator 10 maybe connected appropriately and to suitable slip rings 40 to supply the appropriate alternating potential.

Considering now the operation of the system and the apparatus, it may first of all be pointed out that, if desired, any suitable means may be provided to maintain the current output of the generator substantially constant during the charging of the storage battery 15; as the latter approaches substantially full charge, however, its back E. M. F. rises substantially rapidly so that, if the generator voltage is thereupon kept at an appropriate relatively constant value, the charging current to the battery will taper ofi and the battery thus safeguarded against over-charge. It is at such an appropriate voltage that the regulating apparatus illustratively" charge, the back voltage of the latter approaches or equals the voltage maintained constant by the regulator so that the battery is protected against overcharge.

The windings 25 and 26 operative upon the core 22 are adapted and designed so that, at the desired voltage, the ampere turns provided thereby and thus the pull exerted thereby ,upon the core 22 substantially equal the ampere turns provided by the winding 27 and corresponding pull exerted thereby upon the core 21, respectively. When, therefore, the voltage of the generator is at the desired value, the forces active upon the cores 21 and 22 are substantially -equal to each other, due provision being made for compensating for the effect of the weight 24, and the lever 19 will be maintained in equilibrium and the pressure upon the carbon pile 12 held at a corresponding value. Likewise, at this intended voltage, the filament 29 will be heated to an appropriate and operative degree, and preferably at'such a value that the thermionic device 30 may be made to operate throughout that portion of its operating characteristic which is below the saturation point or below the knee of the characteristic. The adjustable resistance 23 may be utilized to adjust the several parts in order to bring about the conditions above-mentioned.

The winding 25 is preferably proportioned with respect to the winding 26 so that the former contributes about of the necessary ampere turns for operation upon the core 22; this relation of the coils 25 and 26, however, may be varied throughout a wide extent, as may be desired, and furthermore, if desired, the coil 25 may be entirely omitted and the coil 26 adapted and designed to supply the ampere turns necessary for action upon the core 22.

' Assuming, however, that a change in the voltage of the system takes place, due, for example, to a change in the speed of the generator 10, and assuming, furthermore, that the voltage increases, the energization of the solenoid 21-27 will be correspondingly increased, but a part of the thus increased pull exerted by the winding 27 is counteracted by a like increase in the pull exerted by the winding 25 operative upon the core 22. At the same time, however, the same voltage increase causes a corresponding increase in the heating of the cathode 29 of the thermionic device 30, so that the conductivity of the electron path between the two electrodes of the device 30 becomes increased but in a disproportionately greater degree; also the voltage increase is effective to increase the alternating potential supplied by the slip rings 40 and thus to increase in substantially like degree the potential effective in the plate circuit of the thermionic device 30. These changes in heating of the filament 29 and in the potential of the anode 31, each substantially directly proportional to the change in the voltage, bring about, however, due to the characteristics of the thermionic device 30 and due to the portions of the characteristics of the latter throughout which the device 30 is operated, a disproportionately greater increase in the energization of the winding 26.

The ampere turns thus effective on the core 22 are made to relatively greatly preponderate over the ampere turns effective in the winding 27 upon the core 21, so that there is promptly exerted a powerful movement of the lever 29 in a clockwise direction about its pivot 20, thereupon to relieve the pressure on the pile 12, and by correspondingly increasing the resistance in the circuit of the field winding 11, to bring about a reduction to normal of the voltage of the generator 10. The heating of the cathode 29, the potential of the plate 31, and the energization of the several windings active upon the 'two cores, are thus brought back to their normal values, the windings, as will be clear from what has been set forth hereinabove, acting, however, to hold their respective cores in the position into which they have been moved.

Should the change in voltage be in the direction of a decrease in the voltage, substantially the reverse action takes place, it being pointed out that the decrease in the heating of the cathode 29, the effect of which may be and preferably is supplemented by a corresponding decrease in the potential of the plate 31, is made, by virtue of the characteristic of the thermionic device 30, to rapidly diminish the energization of the winding 26 operative upon the core 22 but to a much greater extent than is the corresponding decrease in the energization of the winding 27 operative upon the core 21. The solenoid 21-27 is thus quickly made effective to become powerfully effective to increase the pressure upon the carbon pile 12, and thus to efiect a corresponding rapid increase and restoration to normal of the voltage of the generator 10.

It will thus be seen that, while, when normal electrical conditions are prevailing in the system, the two opposing solenoids are substantially equal in their opposing eifects and maintain the mechanical system in a state of equilibrium, yet the occurrence of a departure from the normal or desired electrical conditions is made to bring about a rapid and powerful preponderance of one of the opposing solenoids over the other. A high degree of sensitivity is thus achieved, and this as well as many other advantages, are achieved, together with the very important advantage of having the two solenoids electrically, magnetically and mechanically of substantially identical construction. Furthermore, also, temperature compensating resistances need not be employed since, irrespective of whatever temperature changes may be balanced out by reason of the windings 25 and 27 being in the same circuit, differences in action of the two solenoids due to differences in temperature become substantially immaterial because of the disproportionately greater response of the thermionic device 30 to a given increment of change in the electrical conditions in the system.

Referring now to Figure 2, it may first be noted that the coil 27 operative upon the core 21 is connected by conductors 41 and 42 directly across the storage battery 15, so as to be energized by the latter when the generator 10 is at rest or operating at such a speed that the main switch 17 is open. The solenoid 21-27 may thus act to maintain the carbon pile 12.under substantial degree of compression under the -conditions pointed out above, thereby avoiding the use of a device such as the weight 24 of Figure 1 and permitting the mechanical system of the regulator of Figure 2 to be substantially perfectly balanced; thus the picking up of the generator promptly is at .all times insured, while as soon as the main switch' 17 is closed, the coil 27 is electrically positioned to be responsive to voltage changes so that its action may be substantially similar to the coil 27 hereinbefore described in connection with Figure 1.

In the arrangement of Figure 2, the primary winding of the transformer 36-37 is supplied with an alternating potential of suitable value by means of the motor generator or converter generally indicated at 43 and adapted to be supplied with energy from the main line conductors 13 and 14, to which it is connected by the conductors 44 and 45 respectively, though it will be understood that the main generator 10 may be made, as illustratively shown and described in connection with Figure 1, to supply the appropriate alternating potential. The winding 25, which coacts with the winding 26, with respect to the core 22 at the opposing end of the lever l9, will be seen to be' connected to be responsive to the changes in the electrical conditions of the system, illustratively set forth as voltage changes. The circuit of the winding 25 will be seen to lead from one side of the generator 10, as the main line conductor 14, thence through conductor 32, filament cathode I 29 and thermionic device 30, adjusting resistance 28, winding 25 and thence by way of conductor 46 to the main line conductor 13 and hence to the other side of thegenerator.

The operation of the apparatus and system of Figure 2 will be clear, 'it is believed, from what has been set forth in detail in connection with Figure 1. Itmay generally be noted, however, that a change in the voltage of the system from the desired value at which the two solenoids are substantially equally opposed in their effect and maintain the mechanical system operated thereby in substantial equilibrium, causes the rapid and relatively great preponderance of the one over the other due to the peculiar characteristics of the thermionic device 30, so that there is achieved not only highly sensitive response of the regulating apparatus but also a powerful actuation thereof to bring about rectification of the changes in the electrical conditions of the system. Difierences in action or effect of various of the coils or windings of the regulating apparatus of Figure 2 need not be compensated for, as is common practice by the inclusion in the respective circuits of relatively high compensating resistances, since the disproportionately greater resultant effect of the thermionic device due to a given increment of change makes such compensation unnecessary. It will furthermore be understood that the strength of the winding 25 with respect to the winding 26 may be proportioned as desired, and that the winding 25 may be omitted if desired. The weaker that the winding 25 is made with respect to the winding 26 (in either Figure 1 or Figure 2) the more rapidly and powerfully is the one solenoid made to preponderate over the other. I prefer, however, to include such a winding as the winding 25 for coaction with the thermionic-controlled winding 26 since, in such case, the winding 26 can be supplied with less energy and the thermionic device 30 as well as the transformer 36-37 may be of less capacity.

It will be understood, however, that if desirable, the resistance 28, hereinabove described in connection with the adjustment or setting of the apparatus, may be constructed or designed to have a temperature compensating action, and that this may be desirable depending upon various practical conditions thatmay be met with.

I wish also to point out that it may, under certain conditions, be desirable to associate with the movable parts of the regulator an appropriate damping device, such as a dash pot, for

which it is desired to maintain in the circuit.-

For example, hysteresis effects, or changes or variability of friction factors in the movable parts of the regulator and like factors oftentimes are the cause of having the regulator maintain a relatively higher or relatively lower standard of regulation with respect to the desired or intended standard, because of the fact that various factors, some of which have been illustratively mentioned above, are of such a nature that it takes the controlling coil or. coils relatively long periods of time to overcome these factors and to bring about conditions, either electrical, mechanical or magnetic, necessary to completely restore and maintain the desired or intended standard of regulation. The characteristics of the thermionic device and the coaction of the latter with the regulator, however, insure the prompt overcoming of such factors as have been above-mentioned illustratively and thus a high degree of closeness and accuracy of regulation are ensured.

In both Figures 1 and 2, I have shown preferred embodiments of an arrangement for insuring against the failure of the thermionic device; I prefer to associate with the thermionic device 30 as many additional thermionic devices as may be desired, and in the drawing I have shown a single additional thermionic device 48, though it is to be specifically understood that additional ones may be associated with respect to the device 30 in substantially the same manner as is the device .48 associated with the device 30 and its respective circuits.

Referring, for example, to Figure 2, the thermionic device 48 is provided with a plate anode 49 connected by conductor 50 to the conductor 35; the latter, it will be noted, is connected also to the plate anode 31 of the device 30 and to one terminal of the secondary winding 36 of the transformer 36-37. The filament cathode 51 of the supplementary thermionic device 48 is connected substantially in parallel with the filament cathode 29 of the device 30, but through a relay-switch generally indicated at 52. This relay-switch 52 may be of any suitable construction and is illustratively shown as being of the solenoid type. It is providedwith a winding 53 connected by conductors 54 and 32 to the main line conductors 13 and 14 respectively, and on the generator side of the main switch. The relay 52 is also provided with a winding 54 which will be seen to be in circuit with the filament cathode 51 and will thus be seen to be energized only when the relay 52 has its switch contacts closed. The winding 53 and its associated movable parts of the relay are so designed that,

, at the maintenance of the normal electrical conditions in the circuit, illustratively shown herein as the maintenance of a predetermined voltage, thewinding 53 is insufflciently energized to cause the closure of the switch contacts of the relay 52. The thermionic device 4815 thus maintained ineffective as long as the thermionic device and its associates parts are operative to maintain the desired electrical conditions in the circuit. Assuming, however, that the thermionic device 30 becomes inoperative, as by way of the filament cathode 29 burning out, for example, then the electrical conditions in the circuit become abnormal and illustratively the voltage of the system will begin to rise, due to the failure of an adequate current flow through the winding 26 in circuit with the thermionic device 30.

Upon a predetermined rise in the voltage, the coil 53 becomes sumciently energized to close the switch contacts of the relay 52 so that the illa- I ment 51 of the thermionic device 48 becomes heated, the resultant current flow thereto and through the coil 54 acting by way of the latter to assist the coil 53 in holding the relay contacts closed. The thermionic device 48 is thus substituted for the ineffective or inoperative device 30, and the temporary abnormality in the electrical conditions is promptly eliminated and the regulation of the system may thereupon proceed as will be clear from what has hereinbefore been described in connection with both Figures 1 and 2. The system and apparatus are thus safeguarded against failure of the thermionic device.

It will thus be seen that there has been provided in this invention a system and apparatus in which the various objects hereinbefore set forth, together with many thoroughly practical advantages, are successfully achieved. It will be seen that the apparatus is of simple and thoroughly practical construction, is capable of inexpensive manufacture, and is'characterized by highly sensitive and powerful but eflicient action when in use. Moreover, it will be seen that the apparatus and system may be readily adjusted to meet varying-conditions of practical use.

As many possible embodiments may be made I of the above invention, and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawing, is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a system of the character described, in combination, a generator; a carbon pile regulator therefor; a storage battery adapted to be charged by said generator; a switch for connecting said storage battery to said generator; and means for controlling said carbon pile regulator, said means including an electromagnetic winding, thermionic means responsive to changes in a function of the output of said generator for controlling the energization of said winding, and an electromagnetic winding for opposing said first-mentioned winding and connected to be energized by current from the battery when said switch is open.

2. In a system of the character described, in combination, a generator; a carbon pile regulator therefor; a storage. battery adapted to be charged by said generator; a circuit connecting said generator and battery; a switch in said circuit for connecting or disconnecting said storage battery to or from said generator; and means for controlling said carbon pile regulator, said means including two voltage responsive windings responsive to the voltage changes across said circuit, and adapted to have opposing effects upon said carbon pile regulator, and means for causing one of said windings to respond in 150 greater degree to a given change in voltage than the other, one of said windings having its connections so that it is energized by current from the storage battery when said switch is open, thereby to maintain said carbon pile under compression when said switch is open.

3. In a system of the character described, in combination, a generator; a carbon pile regulator therefor; a storage battery adapted to be charged by said generator; a switch for connecting said storage battery to said generator; and. means for controlling said carbon pile regulator, said means including two voltage responsive windings responsive to generator voltage when said switch is closed and adapted to have opposing eifects upon said carbon pile regulator, a thermionic device, and means relatingsaid device and one of said windings to cause the said one winding to respond to a given change in voltage in a degree different from the response of the other of said windings to the same change in voltage, one of said windings being connected to be energized by current from said by to maintain said carbon pile under compression when said switch is open.

e. In a system of the character described, in combination, a generator; a carbon pile regulator therefor; a storage battery adapted to be charged by said generator; a switch for connecting said storage battery to said generator; and

means for controlling said carbon pile regulator, said means including a balanced lever, two solenoids adapted to act in opposition to each other upon said carbon pile and through said lever, each of said solenoids being adapted to exert a substantially constant pull at normal energization and throughout the normal range of movement of the movable part thereof, one of said solenoids having its winding connected across said storage battery so as to be energized by the latter and to hold said carbon pile under compression when said switch is open and to be responsive to voltage changes in the system when said switch is closed, and means for "causing the winding of the other soleiibid to be afiected, for a given change in voltage in the system, in greater degree than said last-mentioned solenoid winding.

5. In a system of the character described, in combination, a generator; a carbon pile regulator therefor; a storage battery adapted to be charged by said generator; a switch for connecting said storage battery to said generator; and means for controlling said carbon pile regulator, said means including a balanced lever; two solenoids adapted to act in opposition to each other upon said carbon pile and through said lever, each of said solenoids being adapted to exert a substantially constant pull at normal energization and throughout the normal range of movement of the movable part thereof, one of said solenoids having its winding connected across said storage battery so as to be energized 'by the latter and to hold said carbon pile under compression when said switch is open and to be responsive to voltage changes in the system when said switch is closed, and a thermionic device having a filament cathode connected to be reponsive to voltage changes in the system and having a plate anode for afiecting the energization of the other solenoid winding.

6. In a system of the character described, in combination, a generator; a carbon pile regulator therefor; a storage battery adapted to be charged by said generator; a circuit connecting said generator and said battery; 9, switch in said circuit for connecting or disconnecting said storage battery to or from said generator; and means for affecting said carbon pile regulator, said means including an electromagnetic winding, a second electromagnetic winding having an opposing effect upon said regulator, said windings each being responsive to a function of the energy in said circuit, a device having a pair of spaced electrodes between which ionic conduction takes place, and means relating said device and one of said windings to said circuit to cause said winding to have a greater eflfect than the other, one of said windings being connected to be energized by current from said storage battery when said switch is open, thereby to maintain said carbon pile under compression when said switch is open.

'7. In a system of the character described, in combination, a generator; a carbon pile regulator therefor; a storage battery adapted to be charged by said generator; a circuit connecting said generator and said battery; a switch in said circuit for connecting or disconnecting said storage battery to or from said generator; and means for controlling said carbon pile regulator, said means including a balanced lever, two solenoids responsive to a function of the energy in said circuit and adapted to act in opposition to each other upon said carbon pile and through said lever, each of said solenoids being adapted to exert a substantially constant pull at normal energization and throughout the, normal range of movement of the movable part thereof, one of said solenoids having its winding connected across said storage battery so as to be energized by the latter and to hold said carbon pile under compression when said switch is open and to be responsive to voltage changes in the system when said switch is closed, a device having spaced electrodes between which ionic conduction takes place, and means relating said device and one of said solenoids to said circuit for causing said one solenoid to have a greater efiect than the other.

8. In a system of the character described, in combination, a generator; a carbon pile regulator therefor; a storage battery adapted to be charged by said generator; a switch for connecting said storage battery to said generator; and means for affectingsaid carbon pile regulator, said means including two voltage responsive windings having opposing effects, one of said windings being connected on the generator side of said switch and the other of said windings being connected on the battery side of said switch also 

